Seed propagation takes place during sexual reproduction. The production of seeds through auto-pollination or crossed pollination ensures some genetic variation.
Explanation:
Seeds ensure the existence of genetic variation between plants. There are two general crossing systems in plants, which depend on pollination type.
Self-pollination occurs when the flower pollen is transferred to the same flower stigma, reaching that individual egg to fertilize it. These are autogamous systems.
Crossed pollination occurs when the mature pollen is driven by different pollinator agents from one flower to another, reaching the other flower stigma and fertilizing its eggs. These are xenogamous systems.
Sexual reproduction gives more possibilities to different alleles of a gene that did not appear in one generation to express in the next generation. Both types of pollination allow genetic variation, however by the occurrence of crossed pollination there are more chances to ensure the variability of the species and survival to environmental changes. While by self-pollination there are more chances to express the same genotype of the parental plant. The Xenogamous system has the advantage of avoiding the effects of endogamy in a population.
